Northern Kentucky University’s Griffin Hall houses the College of Informatics, a discipline that merges three different departments: Business Informatics, Communication and Computer Science.

“Once certification is officially received from the United States Green Building Council (USGBC), Griffin Hall will represent NKU’s first LEED-certified building on campus. LEED Silver served as the consistent certification target throughout design and construction, and this target will remain NKU’s minimum certification goal for all future capital building projects. As of October 2011, the USGBC is currently reviewing NKU’s “Design Submission” towards LEED Silver Certification. Please see the NKU GH LEED credits workplan to review a sample LEED credit work plan score card utilized through the design and construction process.

“Griffin Hall chose to employ tested and proven technologies towards LEED certification, and strived to make cognizant, sustainable decisions throughout the design process. Examples of such decisions include occupancy & daylight lighting control sensors and sensor-operated restroom faucets, urinals, and toilets. NKU also decided to install a green roof above the Informatics Commons space and the bank of four classrooms closest to the Student Union, and this green roof covers approximately 23% of the total building roof area. Although the green roof does not qualify for a LEED point by itself, it does promote sustainability by “consuming/reusing” rain water rather than diverting runoff to the storm sewer system. The green roof also helps reduce sunlight heat transmission into the spaces below, which helps reduce energy consumption for cooling,” (NKU Intelligent Building System Energy Dashboard).

Designed by Vivian Llambi and Associates (VLA) and installed by Tecta America Zero company and Green City Resources in 2011, the Northern Kentucky University Greenroof is a part of the Griffin Hall Center for Informatics building, LEED (in process) state-of-the-art IT building. In the Cincinnati/Northern KY area we are mandated to separate storm water from our sewers; this will have the potential to hold some of the over 200,000 gallons of stormwater per year out of our of our sewers and treatment plants. They were also interested in its energy savings and views that were possible from the offices and adjacent buildings.

The Greenroof is above the 2nd floor with two adjacent walls going up 2 more stories. The green roof’s bold elliptical lines, which are embodied by light weight gravel vegetation-free zones contained by aluminum edging, echo the elliptical motif of the dynamic architecture of the building and the pedestrian space of the new West Oval below. In addition to providing the crossing curved lines through which the elliptical design manifests itself, the vegetation-free zones also subdivide the overall planting areas into asymmetrical pockets for singular or double plant species, and serve as paths for maintenance of the planting areas. This intensive vegetated roof includes an 8-inch depth of engineered lightweight planting media and drip irrigation. The plant palette selected was for Zone 6 hardiness, endowing the roof with a wide variety of heights, colors and textures, a staggered bloom sequence, and multi-season interest. Plant material was a mix of native and adaptive plants including the following shrubs, grasses, and perennials:

Calamagrostis x acutiflora ‘Stricta’ (Feather Reed Grass)
Coreopsis verticillata ‘Zagreb’ (Threadleaf Coreopsis)
Helictotrichon sempervirens (Blue Oat Grass)
Hylotelephium spectabile ‘Autumn Joy’ (Stonecrop)
Juniperus procumbens ‘Nana’ (Japanese Garden Juniper)
Lavandula x intermedia ‘Dilly Dilly’ (French Lavender)
Liriope muscari ‘Big Blue’ (Lilyturf)
Panicum virgatum ‘Haense Herms’ (Switchgrass)
Perovskia atriplicifolia (Russian Sage)
Rudbeckia fulgida var. sullivantii ‘Goldsturm’(Blackeyed Susan)
Salvia x sylvestris ‘Mainacht’ (Wood Sage)
Sedum album ‘Coral Carpet’ (White Stonecrop)
Sedum kamtschaticum (Orange Stonecrop)

Membrane used was Sika Sarnafil, 8″ deep rooflite® growing media, and pathways with lightweight rooflite® aggregate.

School was in session during most of the construction, and special allowances for student traffic around the site at all times. The roof has been used for rainwater quality/quantity studies by the students. Cincinnati area has a problem with its stormwater discharge into the Ohio river, one reason for the growth of greenroofs in our region.

The 2011 Sarnafil Contractor of the Year Waterproofing Category Winner Tecta America Zero Company, LLC, based in Cincinnati, OH, took first place in the Waterproofing class for Griffin Hall, Northern Kentucky University (see page 11). The company battled terrible weather conditions and an aggressive schedule for this newly constructed facility, which involved three distinct roof areas and included the vegetated green roof protected by Sika Sarnafil’s G476 waterproofing membrane.